Synopsis: Keep Oxygen Out

Hydrogen storage on carbon materials is strongly affected by the presence of oxygen.
Synopsis figure
A. Sigal et al., Phys. Rev. Lett. (2011)

Hydrogen is a promising source of renewable energy for transportation, but a key challenge is to find a lightweight material to store and extract hydrogen efficiently. Carbon-based compounds such as nanotubes and graphene decorated with metallic atoms have been proposed as storage candidates. First-principles calculations show that these materials, which have a large surface area, favor hydrogen adsorption. However, experiments have not yet found a suitable material that delivers on all the criteria required for applications.

Writing in Physical Review Letters, Agustin Sigal and colleagues from the National University of Córdoba, Argentina, have used density functional theory to calculate the adsorption energy of hydrogen and oxygen on graphene decorated with a variety of metals. Sigal et al. find that oxygen interferes with hydrogen adsorption by blocking the sites where it could take place and by irreversibly oxidizing the metallic sites. Energetically, they find that the most favorable metallic decorations on graphene are those made of nickel, palladium, and platinum. Even in the most promising cases, it is found that oxygen partial pressure must be reduced to an ultrahigh-vacuum level in order to allow efficient hydrogen storage. These findings identify oxygen interference as a major obstacle to storing hydrogen on a carbon scaffold. – Sarma Kancharla


Features

More Features »

Announcements

More Announcements »

Subject Areas

GrapheneMaterials Science

Previous Synopsis

Next Synopsis

Statistical Physics

Touching Gases Settle Down

Read More »

Related Articles

Synopsis: How Diamond-Like Carbon Films Grow
Materials Science

Synopsis: How Diamond-Like Carbon Films Grow

Machine-learning-based molecular dynamics simulations explain the growth mechanism of diamond-like amorphous carbon films. Read More »

Synopsis: Hidden Structure of Plasmons
Plasmonics

Synopsis: Hidden Structure of Plasmons

Calculations of the current density within collective charge oscillations called plasmons reveal a complicated structure that could affect how plasmons reflect off a boundary. Read More »

Synopsis: Stretching Graphene Localizes its Electrons
Graphene

Synopsis: Stretching Graphene Localizes its Electrons

The electrical properties of a graphene bilayer can be tuned by stretching and rotating one of the bilayer’s sheets. Read More »

More Articles